Methanol from atmospheric

Dissolve 20 g of tetra-n-butylammonium iodide in 100 mL of dry methanol and pass this solution through the column at a rate of about 5 mL min - L the effluent must be collected in a vessel fitted with a Carbosorb guard tube to protect it from atmospheric carbon dioxide. Then pass 200 mL of dry methanol through the column. Standardise the methanolic solution by carrying out a potentiometric titration of an accurately weighed portion (about 0.3 g) of benzoic acid. Calculate the molarity of the solution and add sufficient dry methanol to make it approximately 0.1M. 

Extraction of luciferin with methanol from Cypridina frozen with dry ice. The chunks of frozen Cypridina are crushed into small pieces, and extracted with methanol with stirring. Small pieces of dry ice are added as needed to keep the temperature slightly below 0°C and also to prevent the oxidation of luciferin in a CO2 atmosphere. Luciferin is easily extracted into methanol. The mixture is filtered on a Buchner funnel (with suction), protecting the luciferin in a CO2 atmosphere by addition of small pieces of dry ice as needed. 

Chemat and his collaborators [92] reported the UV- and MW-induced rearrangement of 2-benzoyloxyacetophenone, in the presence of bentonite, into l-(o-hydroxy-phenyl)-3-phenylpropane-l,3-dione in methanol at atmospheric pressure (Sch. 14.2). The reaction, performed in the reactor shown in Fig. 14.7, was subject to a significant activation effect under simultaneous UV and MW irradiation this corresponded at least to the sum of the individual effects (Fig. 14.11). The rearrangement, however, was not studied in further detail. Such competitive processes can be described by the diagram in Fig. 14.9, because the product obtained from both types of activation was the same. 

Recently, Liew et al. reported the use of chitosan-stabilized Pt and Pd colloidal particles as catalysts for olefin hydrogenation [51]. The nanocatalysts with a diameter ca. 2 nm were produced from PdCl2 and K2PtCl4 upon reduction with sodium borohydride in the presence of chitosan, a commercial biopolymer, under various molar ratios. These colloids were used for the hydrogenation of oct-1-ene and cyclooctene in methanol at atmospheric pressure and 30 °C. The catalytic activities in term of turnover frequency (TOF mol. product mol. metal-1 h-1)... 

Standardization of 0.1 M Tetrabutylammonium Hydroxide To 10 ml of dimethylformamide add 0.05 ml of a 0.3 % w/v solution of thymol blue in methanol and titrate with the tetrabutylammonium hydroxide solution until a pure blue colour is produced. Immediately add 0.2 g of benzoic acid, stir to effect solution and titrate with the tetrabutylammonium hydroxide solution until the pure blue colour is restored. Protect the solution from atmospheric C02 throughout the titration. The volume of titrant used in the second titration represents the amount of tetrabutylammonium hydroxide required. Each ml of 0.1 M tetrabutylammonium hydroxide Vs is equivalent to 12.21 mg of C7Hg02. 

MacDonald, R. C., and R. Fall, Detection of Substantial Emissions of Methanol from Plants to the Atmosphere, Atmos. Environ., 27A, 1709-1713 (1993). 

Adducts of alkali metal salts prepared in anhydrous alcoholic media generally retain very little alcohol of solvation after being dried under vacuum at room temperature (see Table I). The unusual ability of adducts of D-glucitol to retain alcohol is probably due largely to the great ability of D-glucitol itself to retain solvent. Adducts of alkaline-earth metal salts, however, are more strongly solvated by alcohol than adducts of alkali metal salts. For example,21 lactose CaClj 4 MeOH is relatively stable at 60° at atmospheric pressure under vacuum (< 19 mm. of Hg), a molecule releases only two of the four molecules of methanol. From aqueous alcoholic media, adducts of alkaline-earth metal salts tend to crystallize as hydrates. 

Atmospheric oxidation of formaldehyde, 85 hydroperoxyethane from, 90 hydroxyl in, 85, 91 methanol from, 90 perhydroxyl in, 88... 

IR absorbance spectra of products from, 81 methanol from, 81 peroxyalkyl nitrates from, 84 Atmospheric oxidation of peroxyacetyl radical, 96... 

Methanol has advantages as a carrier of hydrogen because it is a liquid and stable at room temperature. Instead of manufacturing methanol from a fossil fuel such as methane or coal, it would be possible to extract C02 from the atmosphere (Section 15.3.2), produce H2 from solar-based water decomposition, and combine H2 and C02 to CH3OH. The C02 used up to do this would be re-injected to the atmosphere again upon the re-forming of methanol to H2 for the fuel cells, but there would be no net buildup of C02. Further, we would not have to worry about the exhaustion of fossil fuels, which, as far as oil at an acceptable price is concerned, will occur before 2040. 

Figure 15.6 summarizes an electrolytically based solar-hydrogen scheme. The scheme may also involve the extraction of C02 from the atmosphere and the synthesis of methanol from hydrogen. When the methanol is re-formed in vehicles to give H2 for fuel cell electricity, the C02 evolved would balance that absorbed. No fossil fuels would be involved. 

Fig. 15.18. General process scheme for the production of methanol from renewable resources. (Reprinted from S. Stucki, A. Schuler, and M. Constantinescu, Coupled C02 Recovery from the Atmosphere and Water Electrolysis Feasibility of a New Process for Hydrogen Storage, Int. J. Hydrogen Energy, Vol. 20, p. 654, Fig. 1,1995. Reproduced with permission of the International Association for Hydrogen Energy.)...

The production of mono-, di-, and trimethylamines has a number of applications in the chemical industry. Monomethylamine is used in insecticides and surfactants, dimethylamine is used in rubber chemicals, and trimethylamine is used for choline chloride and biocides. Dimethylamine is produced to the greatest extent, followed by mono- and trimethylamine. The methylamines are produced by reaction of methanol and ammonia in the vapor phase over a dehydration catalyst at a temperature of 450°C and from atmospheric to approximately 20.4 atm pressure [30]. The methylamine synthesis reactions are ... 

For the production of methanol, this mixture could be used by the conventional technology directly with no further treatment except adjusting the H2/(CO + C02) ratio to approximately 2 1. For producing hydrogen for ammonia synthesis, however, further treatment steps are needed. First, the required amount of nitrogen for ammonia must be obtained from atmospheric air. This is done by partially oxidizing unreacted methane in the exit gas mixture from the first reactor in another reactor (secondary reforming). 

Example 18.6. A sieve-plate column operating at atmospheric pressure is to produce nearly pure methanol from an aqueous feed containing 40 mole percent methanol. The distillate product rate is 5800 kg/h. (a) For a reflux ratio of 3.5 and a plate spacing of 18 in., calculate the allowable vapor velocity and the column diameter. b) Calculate the pressure drop per plate if each sieve tray is in, thick with j-in, holes on a -in. triangular spacing and a weir height of 2 in. (c) What is the froth height in the downcomer ... 

A sieve-tray column with 15 plates is used to prepare 99 percent methanol from a feed containing 40 percent methanol and 60 percent water (mole percent). The plates have 8 percent open area, in. holes, and 2-in. weirs with segmental downcomers, (a) If the column is operated at atmospheric pressure, estimate the flooding limit based on conditions at the top of the column. What is the F factor and the pressure drop per plate at this limit (Z>) For the flow rate calculated in part (a) determine the F factor and the pressure drop per plate near the bottom of the column. Which section of the column will flood first as the vapor rate is increased ... 

A calcium chloride drying tube is used to protect the contents of the flask from atmospheric moisture, and the reaction mixture is stirred for 18h. Subsequently, 50 mL of methanol is added to the brown mixture, which is stirred for an additional 45 min. The mixture is concentrated to 50 mL by rotary evaporation using an aspirator and a protecting trap, and a solution of 8.2 g (0.05 mol) of ammonium hexafluorophosphate in 40 mL of methanol is added by gravity filtration. The mixture is stirred for 45 min, and the yellow solid that precipitates is collected by suction filtration, washed with a little cold methanol, and dried in vacuo over P Oio- Recrystallization may be effected from acetonitrile-methanol if desired, although the product IX is sufficiently pure for the following reaction. Yield 13.4g (79%). 

---